Internal combustion engine

ABSTRACT

A reciprocating internal combustion, spark-ignition, fuelinjected engine, wherein a single signal source, actuated by the engine, controls fuel injection and ignition in a constant time relationship regardless of engine speed. The start of injection and ignition are separated by a fixed time interval measured and determined by a time delay device which is independent of engine speed.

United States Patent Weise, deceased et all 1 July 11, 11975 lNTERNAL COMBUSTION ENGiNE 2.403.440 7/1946 .lZmSSOH .3 123/32 SP 2,484,009 10/1949 Barber 123/32 SP [76] Inventors, (,arl A. WeIsve, deceased, late of San 2718.883 9/1955 Taylor M 12382 Pedro C3115 Helen Welse, 2,795,214 6/1957 Sl'lOOk .3 123/32 ni r 6 Diamonte n San 2,918,913 12/1959 GUlOI 123/32 EA Pedro, Calif. 90732 2,960.973 11/1960 Davis i 1 123/32 SP 3,020,897 2/1962 Sekine et al. 123/148 E [22] F1169 1972 3,251,351 5/1966 Bowers 123/148 E [21] Appl1N0.:223,381l

Primary Examiner-Charles J. Myhre Related Apphcatmn Dam Assistant ExaminerRonald B. Cox [63] Ctpntgnuaton of Ser. No. 5,214, Jam 23. 1970, Attorney, Agent, or F G F S h ii an one [52 US. Cl. 123/32 SA; 123/32 R; 123/148 E; [57] ABSTRACT [23/117 R A reciprocating internal combustlon, spar1 1gn1t10n, 151 161.1131. F0216 3/00; F02p 5 04 fuel-injected engine, wherein 9 Single Signal Source, [58] Field of Search 123/32 R 32 Sp, 32 SA, actuated by the engine, controls fuel injection and ig- 123/1 17 R nition in a constant time relationship regardless of engine speed. The start of injection and ignition are sep- [56] References Cited arated by a fixed time interval measured and deter- UNITED STATES PATENTS mined by a time delay device which is independent of engine speed. 2,018,159 10/1935 Walker et a1. 123/32 2,306,733 12/1942 Joslyn 123/1 22 Claims, 3 Drawing Figures v J7 \L W/9012 49 29 54/,ap/y/ INTERNAL COMBUSTION ENGINE This is a continuation. of application Serial No. 5,2l l, filed Jan. 23, I970 now abandoned.

BACKGROUND OF THE INVENTION In the field of reciprocating internal combustion engines, many inventions have been produced relating to the control of sparkignition as a function of engine crankshaft angle and speed. In fact, this method of controlling the spark-ignition is widely used in automobiles today.

Additionally, systems have been devised which also control the quantity of fuel injected into a sparkignition engine cylinder as a function of engine speed. Such a system has been shown, for example, in the US. Pat. No. 2,018,159 to Walker et al., issued Oct. 22, I935. Engines utilizing a fuelinjection and ignition control system such as that taught by Walker et al., have controlled each of these operations independently of one another, except insofar as they are both related to crankshaft angle. These engines have proven to be only partly successful in operation since it has been found that fuel injection and ignition spark must not only occur at the proper point in each cycle, but must be correctly timed with respect to each other.

In these engines, the time elapsing between injection and ignition, in fractions of a second varies in accordance with engine speed. On the other hand, the velocity of the injected fuel remains constant, varying only with injection pressure. The distribution and position of the fuel droplets in the combustion chamber at the instant of ignition will therefore change with a variation in engine speed. It is obvious, therefore, that there will be a variety of engine speeds at which injection and ignition occur other than at an interval which allows proper fuel distribution prior to ignition. This results in inefficient engine performance throughout a wide range of engine operating speeds, particularly at part throttle since optimum fuel distribution is usually set to occur at full power speed settings. In fact, under some engine speed conditions, the variation of the interval between injection and ignition can result in misfiring.

None of the prior art engines have taken into account the relationship of the occurrence of ignition to the progress of fuel droplets past the spark plug by means of a simple device which accurately measures and applies a constant time delay between injection and spark ignition regardless of engine speed.

The relationship and the distance between the fuel injection nozzle and the spark plug are fixed by the engine design geometry. If the fuel spray is to be ignited by the spark plug, the spark must occur at the proper instant after the spray has reached the plug. If it occurs too soon, the fuel will not have had time to reach the plug. If it occurs too late, the desired spray pattern will have passed the plug and ignition will, at best, be uncertain.

The duration of fuel injection into a combustion chamber varies with the quantity of fuel injected but the conditions at the start ofinjection, as the fuel spray builds up, are cyclic and therefore predictable. If ignition is caused to occur at a favorable point in the initial portion of the period of injection, reliable ignition will be attained.

SUMMARY OF THE INVENTION This invention relates broadly to the concept of ensuring that ignition occurs within a combustion chamber when the injected fuel is so located and/or distributed as to ensure it is ignited regardless of engine speed.

The invention provides a single signal source, suh as a set of breaker points or other similar device, which controls the injection of a proper amount of fuel into the combustion chamber in accordance with engine speed and crank angle. The signal source also controls a system which ignites the fuel in the combustion chamber at a fixed time after the start of injection so that the fuel is at an optimum distribution within the chamber, regardless of the engine speed or the particular crank angle at the instant of ignition.

The present invention makes use of an electrically controlled fuel injection system in which the injection phase of the cycle is initiated by a low tension or voltage pulse or signal. This same pulse or signal is transmitted to a time delay unit from which, after a predetermined measured time has elapsed, another signal is transmitted to the ignition system and causes an ignition spark discharge to occur at the spark plug.

By adjusting the time delay, the spark can be made to occur just as the fuel droplets at the spark plug have reached the proper concentration to produce a maximum effective ignition. Since the speed of the fuel droplets in their passage from the injection nozzle to the region of the spark plug is independent of engine speed but depends only upon fuel pressure, the proper time delay, once determined for a given fuel pressure will remain absolute for that pressure regardless of engine speed.

In other words, the invention provides a system which produces optimum timing of the ignition spark discharge of an internal combustion, fuel injection, spark ignition engine whereby the time lapse between the beginning of injection and the ignition spark discharge is adjustably controlled only to produce the best results dependent upon the fuel pressure capability. This adjustment can be made before the engine is ever started, for example, and then is held as a fixed constant regardless of engine speed selections or variations.

The single signal source acts to control the fuel injection in a fashion similar to that disclosed in the previously cited patent to Walker et al. The source also acts through a time delay to generate a spark in the combustion chamber at a predetermined interval after commencement of fuel injection. In other words, if it is determined that the optimum distribution of fuel within the combustion chamber occurs 0.001 second after the start of injection, then the time delay can be set so that a spark is generated in the chamber at that instant, regardless of the engine speed. When applied to the internal combustion engines such as those found in automobiles today, a constant injection-ignition time interval will provide highly efficient engine performance throughout the range of speeds of which such engines are capable. Of course, if engine speed is to be varied, the time at which injection occurs will need to be varied relative to cam angle and any readily available means to accomplish that result may be achieved. However, this will in no way alter the novel principle of maintaining the real time interval between start of injection and ignition at a fixed constant to achieve optimum results.

The invention may also be utilized with engines which operate at higher speeds than automobile engines by increasing the injection pressure of the fuel and adjusting the time delay system so as to produce a different,'but constant, injectionignition time interval.

The present invention, which may utilize a mechanical, hydraulic, or electrical injection and ignition time delay system, will result in greater engine efficiency than heretofore possible in economically priced internal combustion engines. Additionally, the invention will cause a decreased quantity of fuel hydrocarbons to be rejected through the exhaust system of the engine. Since ignition can be made to occur when the injected fuel is at its most useful position within the combustion chamber, engine efficiency will also be very high at part throttle when a large quantity of excess air is present within the cylinder. When used in an automobile, efficiency is also improved due to the fact that utilization of a fuel injection and ignition system, independent of airflow, will allow the shutting off of all fuel to the combustion chamber when the engine is decelerated and when it is being used as a brake, such as when a vehicle is traveling downhill.

Through the use of this invention, combustion chamber ignition of injected fuel can be made to occur locally, independent of the overall fuel-air ratio in the combustion chamber. This allows engine operation with excess air in the combustion chamber, as in a Diesel cycle engine. In turn, the result is a high engine efficiency with low pollutant emission. This type of operation makes it possible to run an engine by controlling the quantity of fuel injected per cycle and without having to control the air intake. In other words, it is unnecessary to use a conventional throttle and no fuel need be used during deceleration, thereby producing additional economy and a further reduction of emissions.

Other objects, advantages, and embodiments of the invention will become apparent to those skilled in the art by reference to the Detailed Description and accompanying drawings which illustrate what are presently considered to be preferred embodiments of the best mode contemplated for utilizing the novel principles of the invention as set forth in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic illustration of an engine utilizing the present invention;

FIG. 2 is a more detailed schematic illustration of the electronic control circuitry usedwith the engine shown in FIG. 1; and

FIG. 3 is a schematic illustration of an alternate embodiment of the engine shown in FIG. 1.

DETAILED DESCRIPTION In the schematic illustration of FIG. 1, an engine 11 has a crankshaft 13 extending therethrough in the usual manner. A piston rod 15 is suitably fastened to the crankshaft in a well-known fashion and carries the piston 17 at the upper end thereof. A combustion chamber 19 is formed above the piston 17 and is in communication with an injection passage 21 in which a spark plug 23 and an injection valve 25 are mounted.

The injection valve .25 may be of any suitable type desired, such as that disclosed by Kennedy in US. Pat. No. 1,892,956. The .valve is connected, via a fuel line 27, to. a constant pressure fuel source 29. The fuel source 29 is also similarly connected to otherinjection valves 25, each of which serves a similar combustion chamber in the engine block. i

A pinion gear 31, mounted on the crankshaft l3, suitably meshes with a timing gear 33 which is fixedly mounted on a timing or cam shaft 35 for rotation therewith. The timing shaft 35 is provided with a suitable peripheral cam surface for actuation of a set of breaker points, having contacts 37 and 39, in a well-known manner.

The points 37 and 39 open and close in the conventional manner and, through conventional control means, cause a signal to be provided at the correct shaft angle to initiate fuel injection by means of an injection control unit 41, distributor 47, and electrical injection valve 25. The same signal which initiates injection is applied at the input of the time delay 43 via a line 45.

When the injection control unit 41 receives the signal, it immediately transmits a pulse which, through distributor 47, causes the proper injection valve to open. The magnitude and/or duration of the pulse can be varied by control system 41 to alter the quantity of fuel injected per cycle by altering the length of time that the injection valve is held open. However, this control of the fuel quantity is accomplished only by variation of the length of time that the valve is open; the initiation or start of injection is not varied with respect to the signal or pulse.

At the same time the signal is applied to the injection control system 41, it is also applied to the input of time delay system '43. After a time interval sufficient to allow the injected fuel to enter injection passage 21, proceed to the region of spark plug 23, and build up to the desired concentration, the time delay causes an ignition supply system 49 to fire the spark plug 23 through a distributor 51, thus igniting the fuel.

Referring now to the schematic diagram of FIG. 2, when the points 37 and 39 close, current from a battery 61 passes through the current limiting resistors 53 and 55 to forwardly bias a transistor 57, allowing current from the battery to pass through the transistor to a charging condenser 59 through a variable resistor 63. Since resistor 63 controls the current charge impressed upon the condenser 59, it will, as explained hereafter, serve to control the amount of fuel delivered to the combustion chamber and will therefore act as a speed control.

Instantaneously with the opening of the contacts as cam 35 rotates, the juncture of resistors 53 and 55 will rise to full battery voltage, causing a diode 65 to be forwardly biased to allow current to be passed through a condenser 67 to a silicon-controlled rectifier 69. This action causes the rectifier to fire and discharge the condenser 59 through the coil of the injection valve 25, via distributor 47. The valve is thus raised from its seat for the duration of the condenser discharge. While the valve is raised, fuel under pressure from constant pressure source 29 passes through the valve and is injected into the cylinder; the duration of the injection period,

and hence the amount of fuel injected, is controlled by When the contacts 37 and 39 open, the battery voltage is applied through the time delay network 43, comprising a resistor 75 and a capacitor 77, to a diode 79 in the ignition supply system 49. The network illustrated and described here is of an extremely simple construction. However, it may take many forms, such as those employing a flip-flop" oscillator for accurate time measurement and instantaneous control. The impression of voltage on the diode causes it to be forwardly biased and, through a capacitor 81, to fire a silicon-controlled rectifier 83 for a purpose to be described. A pair of resistors 85 and 87 prevent this action from occurring if point bounce should occur.

The ignition supply 49 generally comprises a transistor operated power supply comprising an oscillator section 89, a transformer 91, and a rectifier 93. This circuitry is directly connected to the battery 61, as shown, to charge a capacitor 95.

When the rectifier 83 is fired in the manner previously described, the capacitor 95 is discharged, through an ignition coil 97 and distributor 51, to fire the spark plug 23.

Thus, the single set of points control the injection of fuel into the engine and the ignition of that fuel on a constant time relationship. If it is found necessary, in certain applications, to change the injection-ignition time interval, the resistor 75 and/or capacitor 77 can be provided to be variable.

Referring now to FIG. 3, an alternate embodiment of the invention has been illustrated in such a manner that elements which are identical to those found in the embodiment of FIG. 1 have been provided with identical identification labels and no further description thereof is believed to be necessary.

As shown in this alternate embodiment, the timing gear 33 is fixed for rotation on a timing shaft 135 which is suitably configured to actuate a fuel pump 173 which draws fuel from a source 129. Fuel leaving the pump passes through a fuel line 126 to a fuel distributor 147 which transfers the fuel to a line 127 for injection into the passage 21 and chamber 19. This system, as shown, obviates the need for an electric injection valve at each cylinder since pump 173 accomplishes the pressurization and metering of the fuel.

A transducer 141 is attached to the fuel line 126 to sense the increase of pressure therein when the pump 173 is actuated by the timing shaft 135. The signal sensed by the transducer 141 is passed through a line 145 to the time delay system 43, producing a result identical to that previously described relative to the embodiment of FIG. 1.

Thus, the applicant has described two embodiments of a concept which may be utilized to vastly improve the operating efficiency of reciprocating internal combustion engines. The concepts embodied in this invention produce a true advancement in the art of internal combustion engines since greater fuel efficiency is provided throughout the operating range of such engines. Many further embodiments, and modifications and alterations thereof utilizing the concepts of the present invention, will be apparent to those skilled in the art, wherefore,

What is claimed as the invention is:

1. The method of controlling the time at which ignition occurs in a fuel-injected, spark ignited, engine comprising the steps of creating a first timing signal during each engine cycle, initiating injection of fuel into a combustion chamber of the engine in response to the first signal,

deriving a second signal from said first signal, which second signal occurs later than said first signal by a predetermined, fixed, clock-time interval after each said creation of the first signal, which clocktime interval does not vary with change of engine speed or the frequency of occurrence of the first signal, and

creating a spark in the combustion chamber of said engine in response to the second signal while the fuel is so positioned in the combustion chamber that it may be ignited by the spark.

2. A fuel injected, spark ignited, engine employing a cyclic combustion process during which fuel is burned in air compressed during each cycle comprising a combustion chamber,

means for generating a signal in timed relation to each cyclic occurrence of a combustion process in said chamber,

means for initiating injection of fuel into said combustion chamber in response to a signal generated by said signal generating means,

an electrical ignition system for igniting fuel injected into said combustion chamber in response to said signal including spark discharge means in said combustion chamber energized by said ignition system and time delay means interposed between said ignition system and said signal generating means for inserting a predetermined fixed clock-time interval of a fraction of a second between the commencement of injection of fuel into said combustion chamber and the generation of a spark at said spark discharge means so that the spark is discharged while the injected fuel is so positioned in said combustion chamber that it may be ignited by the spark thus discharged, which clock-time interval is not altered by changes in engine speed or by engine cyclic progress. 3. The engine of claim 2 wherein said time delay means includes means for adjusting the interval created thereby. 4!. The engine of claim 2 wherein said signal generating means comprises means for generating a low voltage signal. 5. In an internal combustion engine an electrical fuel injection means, an electrical spark ignition means, means for generating an electrical signal to actuate said electrical fuel injection means as air is being compressed in a combustion chamber of said engine into which fuel is injected, and to actuate said electrical spark ignition means, and

time delay apparatus for receiving the signal and storing it until a predetermined and fixed, clock-time interval has elapsed following the actual commencement of entry of fuel into the combustion chamber, which clock-time interval is independent of engine speed and means for transmitting a signal, after the interval has elapsed, from said time delay apparatus to said spark ignition means to cause a spark in the combustion chamber prior to cessation of injection of fuel from the injector of said fuel injection means.

6. The method of operation of a fuel injected, spark ignited, variable speed, internal combustion engine, comprising the stepsof injecting fuel into the combustion chamber of said engine in timed relationship to each engine operating cycle and causing a spark to occur at the sparkignition means in said combustion chamber after the injected fuel has first reached said spark ignition means by generating a spark at said spark ignition means at a predetermined, fixed clock-time interval measured from the commencement of said step of injecting fuel which interval does not vary as engine speed varies but is determined so that ignition occurs at a desired time interval after the fuel first enters the combustion chamber in said engine.

7. The method of claim 6 including the step of varyingthe quantity of fuel injected into the engine in accordance with desired engine speed.

8. The method of claim 7 including the step of maintaining the pressure of the fuel injected into the engine at a constant pressure.

9. The method of claim 1 including the step'of varying the quantity of fuel injected into the engine in accordance with desired engine speed.

10. In a variable speed internal combustion engine,

means for injecting fuel into a combustion chamber in said engine,

means for electrical spark ignition of the fuel injected into the combustion chamber,

means for actuating said fuel injecting means in accordance with a signal generated as a function of engine shaft angle, and

means for actuating said ignition means at the end of a predetermined, constant clock-time interval after the initiation of fuel injection, which interval remains substantially constant regardless of engine speed and is so predetermined that a spark occurs after fuel has first reached the location of said spark ignition means.

11. The engine of claim 10 including means for varying the speed of said engine by adjusting the volume of fuel injected by said fuel injecting means.

l2. The engine of claim 10 wherein said actuating means may be adjusted to alter the interval between actuation of said fuel injecting means and said igniting means.

13. The engine of claim 10 including means for varying the speed of said engine by varying the length of time during which said fuel injecting means is actuated.

14. In an internal combustion engine having a combustion chamber, means for injecting fuel into the combustion chamber, electrical means for spark igniting the injected fuel; and means for actuating said igniting means, the improvement comprising:

means actuated during each cycle of operation of said engine for generating a control signal,

means for actuating the fuel injection means and the spark igniting means in response to said control signal, and

time delay apparatus for delaying the actuation of said igniting means in response to said control signal so that the beginning of the ignition spark always occurs later than the beginning of fuel injection by a predetermined, fixed, clock-time interval and while the injected fuel is so positioned that it may be ignited by said igniting means, which time interval does not vary with changes in engine speed. 15. The apparatus of claim 14 wherein said control signal generating means comprises a set of contacts which are opened and closed by cyclic operation. 16. The apparatus of claim 14 wherein said control signal generating means comprises means actuated by cyclic operation of said engine for creating a force to actuate said fuel injecting means and means for sensing the actuating of said fuel injecting means.

17. A fuel injected, spark ignited, engine employing a cyclic combustion process during which fuel is burned in air compressed during each cycle comprising a combustion chamber,

means in communication with said combustion chamber for injecting fuel thereinto,

a spark ignition means in said combustion chamber for igniting fuel injected into said chamber as it reaches said ignition means,

means for generating a signal in time relationship to each cyclic occurrence of a combustion process in said chamber,

first means for transmitting a signal from said generating means to said fuel injection means to cause fuel to be injected into said combustion chamber in response to receipt of the signal, and

second means for transmitting a signal from said generating means to said spark ignition means to cause a spark to occur at said spark ignition means as injected fuel reaches the latter including time delay apparatus included in said second means for positively delaying the signal transmitted from said generating means to said spark ignition means, which thereby delays actuation of said spark ignition means for a predetermined, fixed, clock-time interval following commencement of fuel injection, which interval does not vary with engine speed variation and is so timed as to delay the commencement of a spark occurrence until injected fuel reaches said spark ignition means.

18. The method of causing the occurrence of combustion in the combustion chamber of a fuel injected, spark ignited engine comprising the steps of generating a signal in timed relation to the cyclic occurrence of a combustion process in said chamber,

directing the signal thus generated to the fuel injection means in said engine to initiate injection of fuel into the combustion chamber upon receipt of the signal,

directing the signal thus generated to a time delay apparatus,

storing a signal in the time delay apparatus for a predetermined, clock-time interval, which clock-time interval is fixed and constant regardless of changes in engine speed,

releasing a signal from the time delay apparatus upon expiration of said clock-time interval, and

directing the signal thus released to the spark ignition means, to cause the commencement of a spark thereat while the injected fuel is so positioned that it may be ignited by said spark ignition means, only upon expiration of the clock-time interval.

119. In an internal combustion engine,

a combustion chamber,

a fuel injection system which injects fuel into said combustion chamber,

a spark ignition system for igniting fuel injected into said combustion chamber, and

means for sensing the start of the fuel injection process and, in response to said sensing, for actuating said spark ignition system at a predetermined, fixed clock-time interval thereafter, which interval is so predetermined that a spark is created in said combustion chamber after the fuel has first reached the location of said spark ignition means, and is not altered by changes in engine speed.

20. In an internal combustion engine,

a combustion chamber,

a fuel injection system which initiates injection of fuel into said combustion chamber as air is being compressed therein,

a spark ignition system for igniting fuel injected into said combustion chamber, and

means for sensing the start of the fuel injection process and, in response to said sensing, for actuating said spark ignition system at a predetermined, fixed clock-time interval thereafter, which interval is so predetermined that a spark is created in said combustion chamber after fuel has first reached the location of said spark ignition means and is not altered by changes in engine power shaft angle.

21. The method of operation of a fuel injected, spark ignited, variable speed, internal combustion engine, comprising the steps of generating a signal in timed relation to the cyclic occurrence of a combustion process in a combustion chamber of the engine,

directing the signal thus generated to the fuel injection means in the engine to initiate injection of fuel into the combustion chamber upon receipt of the signal,

directing the signal to the spark ignition means in the engine to create a spark in the combustion chamber, but

delaying the actuation of said spark ignition means for a predetermined, fixed clock-time interval after initiation of injection to create the spark after the injected fuel has first reached the spark ignition means 22. In a variable speed internal combustion engine means for injecting fuel into a combustion chamber in said engine,

means for electrical spark ignition of the fuel injected into the combustion chamber,

means for actuating said fuel injecting means in accordance with a signal generated as a function of engine shaft angle, and

adjustable means for actuating said ignition means at the end of a predetermined, constant clock-time interval after the initiation of fuel injection so that the injected fuel is so positioned in the combustion chamber that it may be ignited by said ignition means, which interval remains substantially constant throughout the range of engine speeds but may be altered in accordance with desired engine 

1. The method of controlling the time at which ignition occurs in a fuel-injected, spark ignited, engine comprising the steps of creating a first timing signal during each engine cycle, initiating injection of fuel into a combustion chamber of the engine in response to the first signal, deriving a second signal from said first signal, which second signal occurs later than said first signal by a predetermined, fixed, clock-time interval after each said creation of the first signal, which clock-time interval does not vary with change of engine speed or the frequency of occurrence of the first signal, and creating a spark in the combustion chamber of said engine in response to the second signal while the fuel is so positioned in the combustion chamber that it may be ignited by the spark.
 2. A fuel injected, spark ignited, engine employing a cyclic combustion process during which fuel is burned in air compressed during each cycle comprising a combustion chamber, means for generating a signal in timed relation to each cyclic occurrence of a combustion process in said chamber, means for initiating injection of fuel into said combustion chamber in response to a signal generated by said signal generating means, an electrical ignition system for igniting fuel injected into said combustion chamber in response to said signal including spark discharge means in said combustion chamber energized by said ignition system and time delay means interposed between said ignition system and said signal generating means for inserting a predetermined fixed clock-time interval of a fraction of a second between the commencement of injection of fuel into said combustion chamber and the generation of a spark at said spark discharge means so that the spark is discharged while the injected fuel is so positioned in said combustion chamber that it may be ignited by the spark thus discharged, which clock-time interval is not altered by changes in engine speed or by engine cyclic progress.
 3. The engine of claim 2 wherein said time delay means includes means for adjusting the interval created thereby.
 4. The engine of claim 2 wherein said signal generating means comprises means for generating a low voltage signal.
 5. In an internal combustion engine an electrical fuel injection means, an electrical spark ignition means, means for generating an electrical signal to actuate said electrical fuel injection means as air is being compressed in a combustion chamber of said engine into which fuel is injected, and to actuate said electrical spark ignition means, and time delay apparatus for receiving the signal and storing it until a predetermined and fixed, clock-time interval has elapsed following the actual commencement of entry of fuel into the combustion chamber, which clock-time interval is independent of engine speed and means for transmitting a signal, after the interval has elapsed, from said time delay apparatus to said spark ignition means to cause a spark in the combustion chamber prior to cessation of injection of fuel from the injector of said fuel injection means.
 6. The method of operation of a fuel injected, spark-ignited, variable speed, internal combustion engine, comprising the steps of injecting fuel into the combustion chamber of said engine in timed relationship to each engine operating cycle and causing a spark to occur at the spark ignition means in said combustion chamber after the injected fuel has first reached said spark ignition means by generating a spark at said spark ignition means at a predetermined, fixed clock-time interval measured from the commencement of said step of injecting fuel which interval does not vary as engine speed varies but is determined so that ignition occurs at a desired time interval after the fuel first enters the combustion chamber in said engine.
 7. The method of claim 6 including the step of varying the quantity of fuel injected into the engine in accordance with desired engine speed.
 8. The method of claim 7 including the step of maintaining the pressure of the fuel injected into the engine at a constant pressure.
 9. The method of claim 1 including the step of varying the quantity of fuel injected into the engine in accordance with desired engine speed.
 10. In a variable speed internal combustion engine, means for injecting fuel into a combustion chamber in said engine, means for electrical spark ignition of the fuel injected into the combustion chamber, means for actuating said fuel injecting means in accordance with a signal generated as a function of engine shaft angle, and means for actuating said ignition means at the end of a predetermined, constant clock-time interval after the initiation of fuel injection, which interval remains substantially constant regardless of engine speed and is so predetermined that a spark occurs after fuel has first reached the location of said spark ignition means.
 11. The engine of claim 10 including means for varying the speed of said engine by adjusting the volume of fuel injected by said fuel injecting means.
 12. The engine of claim 10 wherein said actuating means may be adjusted to alter the interval between actuation of said fuel injecting means and said igniting means.
 13. The engine of claim 10 including means for varying the speed of said engine by varying the length of time during which said fuel injecting means is actuated.
 14. In an internal combustion engine having a combustion chamber, means for injecting fuel into the combustion chamber, electrical means for spark igniting the injected fuel; and means for actuating said igniting means, the improvement comprising: means actuated during each cycle of operation of said engine for generating a control signal, means for actuating the fuel injection means and the spark igniting means in response to said control signal, and time delay apparatus for delaying the actuation of said igniting means in response to said control signal so that the beginning of the ignition spark always occurs later than the beginning of fuel injection by a predetermined, fixed, clock-time interval and while the injected fuel is so positioned that it may be ignited by said igniting means, which time interval does not vary with changes in engine speed.
 15. The apparatus of claim 14 wherein said control signal generating means comprises a set of contacts which are opened and closed by cyclic operation.
 16. The apparatus of claim 14 wherein said control signal generating means comprises means actuated by cyclic operation of said engine for creating a force to actuate said fuel injecting means and means for sensing the actuating of said fuel injecting means.
 17. A fuel injected, spark ignited, engine employing a cyclic combustion process during which fuel is burned in air compressed during each cycle comprising a combustion chamber, means in communication with said combustion chamber for injecting fuel thereinto, a spark ignition means in said combustion chamber for igniting fuel injected into said chamber as it reaches said ignition means, means for generating a signal in time relationship to each cyclic occurrence of a combustion process in said chamber, first means for transmitting a signal from said generating means to said fuel injection means to cause fuel to be injected into said combustion chamber in response to receipt of the signal, and second means for transmitting a signal from said generating means to said spark ignition means to cause a spark to occur at said spark ignition means as injected fuel reaches the latter including time delay apparatus included in said second means for positively delaying the signal transmitted from said generating means to said spark ignition means, which thereby delays actuation of said spark ignition means for a predetermined, fixed, clock-time interval following commencement of fuel injection, which interval does not vary with engine speed variation and is so timed as to delay the commencement of a spark occurrence until injected fuel reaches said spark ignition means.
 18. The method of causing the occurrence of combustion in the combustion chamber of a fuel injected, spark ignited engine comprising the steps of generating a signal in timed relation to the cyclic occurrence of a combustion process in said chamber, directing the signal thus generated to the fuel injection means in said engine to initiate injection of fuel into the combustion chamber upon receipt of the signal, directing the signal thus generated to a time delay apparatus, storing a signal in the time delay apparatus for a predetermined, clock-time interval, which clock-time interval is fixed and constant regardless of changes in engine speed, releasing a signal from the time delay apparatus upon expiration of said clock-time interval, and directing the signal thus released to the spark ignition means, to cause the commencement of a spark thereat while the injected fuel is so positioned that it may be ignited by said spark ignition means, only upon expiration of the clock-time interval.
 19. In an internal combustion engine, a combustion chamber, a fuel injection system which injects fuel into said combustion chamber, a spark ignition system for igniting fuel injected into said combustion chamber, and means for sensing the start of the fuel injection process and, in response to said sensing, for actuating said spark ignition system at a predetermined, fixed clock-time interval thereafter, which interval is so predetermined that a spark is created in said combustion chamber after the fuel has first reached the location of said spark ignition means, and is not altered by changes in engine speed.
 20. In an internal combustion engine, a combustion chamber, a fuel injection system which initiates injection of fuel into said combustion chamber as air is being compressed therein, a spark ignition system for igniting fuel injected into said combustion chamber, and means for sensing the start of the fuel injection process and, in response to said sensing, for actuating said spark ignition system at a predetermined, fixed clock-time interval thereafter, which interval is so predetermined that a spark is created in said combustion chamber after fuel has first reached the location of said spark ignition means and is not altered by changes in engine power shaft angle.
 21. The method of operation of a fuel injected, spark ignited, variable speed, internal combustion engine, comprising the steps of generating a signal in timed relation to the cyclic occurrence of a combustion process in a combustion chamber of the engine, directing the signal thus generated to the fuel injection means in the engine to initiate injection of fuel into the combustion chamber upon receipt of the signal, directing the signal to the spark ignition means in the engine to create a spark in the combustion chamber, but delaying the actuation of said spark ignition means for a predetermined, fixed clock-time interval after initiation of injection to create the spark after the injected fuel has first reached the spark ignition means.
 22. In a variable speed internal combustion engine means for injecting fuel into a combustion chamber in said engine, means for electrical spark ignition of the fuel injected into the combustion chamber, means for actuating said fuel injecting means in accordance with a signal generated as a function of engine shaft angle, and adjustable means for actuating said ignition means at the end of a predetermined, constant clock-time interval after the initiation of fuel injection so that the injected fuel is so positioned in the combustion chamber that it may be ignited by said ignition means, which interval remains substantially constant throughout the range of engine speeds but may be altered in accordance with desired engine operation. 